EU: Attack was on our open democratic society

In a joint statement, the leaders of the EU said they "stand firm with Belgium in solidarity and are determined to face this threat together with all necessary means."

"This latest attack only strengthens our resolve to defend the European values and tolerance from the attacks of the intolerant. We will be united and firm in the fight against hatred, violent extremism and terrorism."

"The European Union mourns the victims of today's terrorist attacks in Brussels. It was an attack on our open democratic society. "